Method and system for deflection of a body lumen

ABSTRACT

A positioning device configured for introduction within a body lumen. Some embodiments include a catheter shaft with a longitudinal axis; an expandable element coupled along a length of the shaft, the expandable element being substantially thin and flexible in an unexpanded state and exerting a gentle outward force in an expanded state; and a deflection mechanism located within the shaft, wherein the deflection mechanism is flexible when in a non-deflected state and wherein, in the deflected state, the deflection curves in a predetermined lateral direction such that the positioning device laterally deflects the body lumen. In some embodiments, the deflection is a lateral curve that moves the body lumen away from a surgical site, such as a cardiac ablation site.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/462,377 titled “SYSTEM AND METHOD FOR DEFLECTION OF A BODY LUMEN,”filed May 20, 2019 (which issued as U.S. Pat. No. 11,298,203 on Apr. 12,2022), which is a national-phase filing of, and claims priority benefitof, PCT Patent Application No. PCT/US2017/063171, filed Nov. 23, 2017 byGregory G. Brucker, et al., and titled “System and method for deflectionof a body lumen,” which claims priority benefit, including under 35U.S.C. § 119(e), of U.S. Provisional Patent Application No. 62/426,223,filed Nov. 23, 2016 by Gregory G. Brucker, et al., and titled “Systemand method for deflection of a body lumen,” each of which isincorporated herein by reference in its entirety.

FIELD OF THE INVENTION

Embodiments of the present invention relate generally to a catheter fordeflection of a lumen within a body cavity for the purpose ofrepositioning a body lumen to substantially reduce or eliminateunintended damage to a bodily organ during delivery of therapy, such asmoving the esophagus away from the heart during an ablation procedurefor treatment of atrial fibrillation to minimize potential for formationof an atrial-esophageal fistula. The present invention includes anexpansion catheter for enlarging a body lumen to reduce its elasticityand a deflection mechanism attached to or located within the expansioncatheter to move the body lumen from its natural position within thebody.

BACKGROUND OF THE INVENTION

Devices for deflection of a body lumen can be classified by themechanism by which deflection occurs, namely: mechanical or expandable.Mechanical deflection uses a pre-curved element such as a styletinserted into a flexible tube placed within a body lumen to reposition aportion of the body lumen within a body cavity. Alternatively, a wirecan be housed within a flexible tube and wire tension used to curve thetube and move a body lumen a desired distance. Expandable deflectionuses an element, for example a balloon, which contains a predefinedcurvature such that upon expansion from a smaller diameter to a largerdiameter the body lumen is repositioned by virtue of the curvature ofthe expanded element. Both deflection mechanisms have limited clinicalbenefit for repositioning a body lumen within a body cavity, primarilydue to the elasticity of most body lumens. For example, for treatment ofatrial fibrillation using cardiac ablation therapies, it is oftendesirable to reposition the esophagus in regions near the posterior wallof the left atrium to prevent the formation of an atrial-esophagealfistula which can be fatal or to prevent periesophageal vagus plexusinjury. The diameter and elasticity of the esophagus has limited theability of aforementioned deflection methods to adequately repositionthe esophagus to reduce clinical risk, thereby limiting their clinicalvalue.

For mechanical devices that typically use tubes and a deflection meanscontained therein, the diameter of the device is generally smaller thanthe lumen into which it is inserted. Because of the diameter differencebetween the device and the body lumen, the initial deflection of amechanical device first moves to engage some aspect of a luminal wallwhich then, because of the concentrated force loadings on the luminalwall and elasticity of the body lumen, changes the lateralcross-sectional profile of the body lumen from circular to ellipsoidalwith an increasingly higher aspect ratio. Effectively, even though thereis significant lateral movement of the device, the movement of thecenterline of the body lumen relative to other body structures issubstantially reduced. Larger-diameter tubes can be used to minimizethese aforementioned effects, but, as devices become larger, they alsobecome stiffer, making insertion more complicated and risk of collateraltissue damage higher. For example, in esophageal applications,deflection devices are normally inserted either through the nose orthroat, which limits device diameters to 3 mm (0.118 inch) and 9 mm(0.354 inch), respectively, while the diameter of the esophagus rangesfrom 15 to 30 mm (0.591 to 1.181 inch). In general this has limitedlateral movement of the esophagus to about 2.0 cm (0.787 inch), with amore desirable range being 3.0 to 4.0 cm (1.18 to 1.57 inch).

For expandable devices which have an element which enlarges toapproximately the diameter of the body lumen, the expandable elementgenerally has a preset curvature when enlarged. During use, thepre-curved element first expands to engage a body lumen and then, uponcontinued expansion, deflects the body lumen from its normal pathwaythrough a body cavity. The most common implementations of this type ofdeflection mechanism are pre-shaped balloons or curved wire meshes. Theadvantage of these devices is they maintain the diameter and circularityof the body lumen so that curvature of the device results in moremovement of the centerline of the body lumen from its normal pathway.The disadvantage of expandable devices is the higher forces required fordeflection, which translates into higher-pressure balloons or thickermesh wires, resulting in stiffer devices and larger diameter crossingprofiles in their unexpanded state, both possibly damaging to the bodylumen and clinically undesirable.

In addition to the aforementioned disadvantages, both mechanicaldeflection devices and expandable devices require additional steps whenrepositioning the deflection device within a body lumen. Since thedeflection mechanism is an integral part of the device, the deflectiondevice must be returned to its neutral state before repositioning withina body lumen. At a minimum, this requires additional procedural time,which potentially exposes the patient to additional risk duringmanipulation of the deflection device.

U.S. Pat. No. 7,621,908, issued Nov. 24, 2009, titled “Catheter forManipulation of the Esophagus” by Steven W. Miller, which isincorporated herein by reference in its entirety, describes anesophageal catheter for displacing and fixing the position of theesophagus in relation to the atrium of the heart which is composed of along flexible tube to be inserted into the esophagus. A control wire isassociated with the tube to change the shape of the catheter anddisplace the esophagus relative to the heart to reduce the risk of anesophageal fistula resulting from atrial RF ablation.

U.S. Pat. No. 8,529,443, issued Sep. 10, 2013, titled “Nasogastric Tubefor Use during an Ablation Procedure” by James D. Maloney, which isincorporated herein by reference in its entirety, describes embodimentsof the present invention to provide a nasogastric tube for deflecting anesophagus during an ablation procedure. According to one embodiment, thenasogastric tube includes a flexible tube that includes at least onelumen having proximal and distal ends, and an esophageal deflectorpositioned within the at least one lumen and configured to bemechanically actuated to assume a curved profile so as to deflect aportion of the tube between the proximal and distal ends. The esophagealdeflector is configured to deflect the portion of the tube proximate toa retrocardiac portion of the esophagus such that the retrocardiacportion of the esophagus is deflected away from an ablation site.

U.S. Pat. No. 8,273,016, issued on Sep. 25, 2012, titled “EsophagealIsolation Device” by Martin F. O'Sullivan, which is incorporated hereinby reference in its entirety, describes an esophageal-isolation catheterfor deflecting an esophagus of a patient away from an ablation site inthe left atrium of the patient's heart. The catheter includes anelongated catheter body and a deflectable section. In one embodiment,the catheter includes a deflectable intermediate section mounted at thedistal end of the catheter body and a generally straight tip sectionmounted at the distal end of the intermediate section. In thisembodiment, the catheter includes two pull wires, one anchored proximalthe other. The intermediate section deflects to form a generallyC-shaped or omega-shaped (Ω-shaped) curve. In an alternative embodiment,the catheter includes a deflectable tip section mounted at the distalend of the catheter body. In this embodiment, the catheter includes onlyone pull wire. The tip section carries a tip electrode having anatraumatic design to prevent damage to the esophagus upon deflection.

U.S. Pat. No. 8,454,588, issued on Jun. 4, 2013, titled “Method andApparatus to Prevent Esophageal Damage” by Gregory B. Rieker et al.,which is incorporated herein by reference in its entirety, describes anapparatus for moving the esophagus which includes an elongate bodyhaving a distal tip, a controlled curvature section, and a flexiblesection. A handle is coupled to the flexible section to adjust thecurvature of the controlled curvature section. The length of thecontrolled curvature section is less than the length of the thoracicportion of the esophagus. Further, a method of adjusting the curvatureof the esophagus during a therapeutic procedure in a treatment areaoutside of the esophagus includes positioning within the esophagus anelongate body having a distal tip, a controlled curvature section, and aflexible section and adjusting the curvature of the controlled curvaturesection to increase the distance between the esophagus and a treatmentarea outside of the esophagus.

U.S. Pat. No. 9,119,927, issued Sep. 1, 2015, titled “Apparatus andMethod for Intubating Humans and Non-Human Animals” by Jerry B.Ratterree et al., which is incorporated herein by reference in itsentirety, describes an apparatus and a corresponding method forintubating a human or non-human animal patient. In some embodiments, thepresent invention is used in the field of anesthesia and emergencymedicine. In some embodiments, the present invention provides anintubation tube that includes an integrated Blaine Bafflex System havinga plurality of blains for sealing the trachea, wherein the intubationtube is formed from a single material. In some embodiments, the shapeand outer circumference of each blaine of the system is selectedaccording to the desired use of the intubation tube (e.g., forintubating a pediatric patient or an adult patient or for intubating asmall animal or a large animal). In some embodiments, the distancebetween successive blaines is selected such that, when the intubationtube is inserted into the patient and the blaines bend, none of theblaines overlap with their nearest neighbor.

U.S. Patent Publication 2011/0082488, published on Apr. 7, 2011, titled“Intra-Esophageal Balloon System” by Imran K. Niazi, which isincorporated herein by reference in its entirety, discloses a device andsystem for selective inflation of an inflatable body, such as a balloon,received through an oral cavity and into the esophagus of a patient. Theinflatable body is operably coupled to a pressurized fluid source. Theinflatable body has a relatively flexible portion and a relativelyinflexible portion. When pressurized fluid is delivered to the body toinflate the body, the flexible portion expands more than the inflexibleportion, resulting in asymmetrical expansion and movement of theesophagus away from the ablation site to avoid accidental injury whileperforming a procedure on the patient's left atrium. This movement maybe opposite from or directly away from the heart or, alternatively, maybe sideways relative to the heart to a location in which the esophagusis interposed between the ablation site and the phrenic nerve. Thesupplied fluid may be radio-opaque liquid to allow for imaging thereofto assist in positioning the balloon. The liquid may additionally berelatively cool as compared to the patient's body temperature so serveas a heat sink against heat applied to surrounding areas.

U.S. Patent Publication 2015/0245829, published on Sep. 3, 2015, titled“Expandable Device for Positioning Organs” by Shawn K. Fojtik, which isincorporated herein by reference in its entirety, discloses apositioning device configured to selectively position or otherwisemanipulate one or more organs within the body of a subject. Thepositioning device includes a shaped expandable element that isconfigured to be selectively transitioned between an unexpanded, orcollapsed, state and an expanded state. While in the expanded state, theexpandable element repositions or otherwise manipulates an organ.Systems that include positioning devices are also disclosed, as aremethods for positioning or otherwise manipulating organs.

There is a need for an improved system for deflection of a body lumen,for use in positioning the lumen for surgical procedures and otherpurposes.

SUMMARY OF THE INVENTION

In some embodiments, the present invention provides an apparatus fordisplacing a portion of a flexible target lumen, wherein the apparatusincludes: a catheter shaft having a first catheter-shaft lumen withinthe catheter shaft, the first catheter-shaft lumen extending through atleast a portion of length of the catheter shaft, a plurality ofinflatable and deflatable balloons located along the catheter shaft andoperably coupled to the first catheter-shaft lumen and configured toexpand in diameter within the flexible target lumen to form an expandedfirst portion of the apparatus, and a lateral deflection mechanismoperably coupled to the catheter shaft and configured to laterallydeflect the expanded first portion of the apparatus while within theflexible target lumen in order to laterally deflect the flexible targetlumen.

Some embodiments of the current invention for manipulation of a bodilylumen are designed to combine a mechanical approach with an expandableelement approach to obtain the benefits of more reliable positioning,larger body-lumen deflection and easier clinical use. These benefits arederived from three features that collectively provide these desirableclinical advantages. First, is an expansion catheter that includes acatheter shaft with one or more expansion elements attached to its outersurface. The expansion element(s) serve to enlarge a body lumen toreduce its elasticity and deformability when manipulated effectivelyfixing the relationship between the expansion catheter and a body lumen.Second, a deflection mechanism resides within the catheter shaft which,when manipulated, causes the catheter shaft to deviate from its neutralstate to a curved state in which at least a portion of the cathetershaft is displaced laterally while simultaneously displacing the bodylumen in contact with the expansion elements. Third, in embodimentswhere the expansion catheter and deflection mechanism are separateentities, the expansion catheter without a deflection mechanism is moreeasily introduced and positioned within a body lumen, resulting in lessdamage to a body lumen. Once the deflection mechanism is inserted intothe expansion catheter, changing the location of the deflected portionof the expansion catheter relative to body structures is easilyaccomplished with the expansion elements fully expanded.

In one embodiment of the current invention which incorporates multipleballoons as expansion elements and a deflection catheter fordisplacement of a body lumen, when used in conjunction with a cardiacablation procedure for treatment of atrial fibrillation, proceeds asfollows: A guidewire is passed through a nasal passageway or mouth intothe esophagus. An expansion catheter with its balloons in a deflatedstate is passed over the guidewire into the esophagus and the expansioncatheter positioned at a desired location. The balloons are theninflated individually or collectively to the approximate diameter of theesophagus, fixing the catheter shaft within the esophagus. Theguidewire, if used, is removed from the expansion catheter and adeflection mechanism is inserted into the central lumen of the expansioncatheter and positioned therein relative to the left atrium at thedesired location for repositioning of the esophagus. The deflectionmechanism is then caused to curve, and the degree and plane of curvatureevaluated using an imaging modality, such as fluoroscopy. In someembodiments, the location and orientation of the deflected portion ofthe expansion catheter is altered by moving the deflection mechanismlongitudinally or rotating it circumferentially within the cathetershaft. At the completion of the procedure, the deflection mechanism isreturned to its neutral position and removed from the expansioncatheter. In some embodiments, the balloons are then deflated and theexpansion catheter removed from the esophagus and the mouth or nasalpassageway. In some embodiments of the present invention, deflection ofother body lumens such as veins, arteries, urethra, fallopian tubes andvarious segments of the gastrointestinal tract is accomplished using thepresent invention.

In some embodiments, numerous benefits are derived from the use of thecurrent invention in various clinical applications. For example, incardiac ablations for treatment of atrial fibrillation, the esophaguscan be deflected away from its natural position relative to the leftatrium to reduce the probability of forming an atrial-esophageal fistulaor causing periesophageal vagal plexus injury. In some embodiments,these benefits are derived from a combination of one or more of thefeatures that are summarized as follows: First, in some embodiments, theuse of multiple small balloons allows the expansion catheter to maintainits alignment within esophagus during deflection. Second, in someembodiments, the use of a plurality of small balloons provides morepoints of articulation along the length of the expansion catheter, whichallows the catheter shaft to flex more easily to obtain the desiredcurvature and degree of deflection. Third, in some embodiments, becausethe balloons are used primarily for the purpose of maintainingalignment, the balloon pressure required during operation is lower thanthat needed if the balloons were also used as the primary means ofdeflection. This allows for balloons with thinner walls, which areinherently more flexible and have a smaller crossing profile. Fourth, insome embodiments, because the deflection mechanism is a detachableelement within the expansion catheter, and the expansion catheter isinserted separately, the expansion catheter is made to be more flexiblefor easier entry, navigation and passage into a body lumen, especiallyin the presence of significant tortuosity. Fifth, in some embodiments,the lumen within the expansion catheter that houses the deflectionmechanism also serves as a guidewire lumen during insertion into a bodylumen, thus reducing trauma to a body lumen. Sixth, in some embodiments,movement of the deflection mechanism independent of the expansioncatheter allows repositioning of the curvature relative to a bodystructure to be accomplished more easily while the balloons remaininflated.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is an isometric view that illustrates an expansion catheter 101with balloons 170 deflated and a guidewire inserted and the expansioncatheter in its neutral state aligned along a longitudinal axis,according to some embodiments of the present invention.

FIG. 1B is an isometric view that illustrates expansion catheter 101with balloons 170 inflated and a deflection mechanism inserted and theexpansion catheter curved relative to its longitudinal axis in a neutralstate, according to some embodiments of the present invention.

FIG. 2A1 is a cross-sectional view of expansion catheter 101 throughplane 2A1-2A1 shown in FIG. 1B, according to some embodiments of thepresent invention.

FIG. 2A2 is a cross-sectional view of expansion catheter 101 throughplane 2A2-2A2 shown in FIG. 1B, according to some embodiments of thepresent invention.

FIG. 2B is a longitudinal sectional view of expansion catheter 101through plane 2B-2B of the expansion catheter 101 of FIG. 1B, accordingto some embodiments of the present invention.

FIG. 2C is a cross-sectional view hub 140 of an expansion catheter 101,according to some embodiments of the present invention.

FIG. 2D is a side view of a central portion 220 of an expansion catheter204 that uses a single balloon 270 that is mechanically segmented toform a plurality of expanded bulbous portions 270.1, 270.2, . . . 270.Nalong a catheter 221, according to some embodiments of the presentinvention.

FIG. 3A is a longitudinal cross-sectional view of a deflection mechanism300 for insertion into an expansion catheter, according to someembodiments of the present invention.

FIG. 3B is a cross-sectional view at section 3B-3B of FIG. 3A, whichillustrates a rectangular wire as an element of a deflection mechanism,according to some embodiments of the present invention.

FIG. 3C illustrates a deflection mechanism in a curved configuration,according to some embodiments of the present invention.

FIGS. 3D and 3E illustrate passive stylets each with a single plane ofcurvature, according to some embodiments of the present invention.

FIG. 3F illustrates a passive stylet with two curves in a single planeof curvature, according to some embodiments of the present invention.

FIG. 3G illustrates a passive stylet with two curves in two differentplanes of curvature, according to some embodiments of the presentinvention.

FIG. 3H is a side view of the deflection section of a deflection device308 having an integral expansion catheter with an integral deflectionmechanism contained within one lumen, according to some embodiments ofthe present invention.

FIG. 3i is a cross-section view of a deflection device catheter shaft321 that includes an expansion catheter with an integral pull wirecontained within one lumen, according to some embodiments of the presentinvention.

FIG. 4A is a side-view cross-section view of a body lumen 99 thatillustrates lateral displacement of the body lumen 99 withoutdeformation of the body lumen 99, according to some embodiments of thepresent invention.

FIG. 4B is a side-view cross-section view of a body lumen 99 thatillustrates both lateral displacement and deformation of the body lumen99, according to some embodiments of the present invention.

FIG. 5A is a side view of a deflection device 520 using a pre-shapedwire spline as an expandable element, according to some embodiments ofthe present invention.

FIG. 5B is a side view of a deflection device 530 using a single balloon571 that is helically wrapped with a metal strap 561, according to someembodiments of the present invention.

FIG. 6A1 is a side view of an expansion catheter 620 using a singleballoon 671 wrapped in a spiral pattern around a catheter shaft, shownwith balloon 671 deflated, according to some embodiments of the presentinvention.

FIG. 6A2 is a side view of an expansion catheter 620 using a singleballoon 671 wrapped in a spiral pattern around a catheter shaft, shownwith balloon 671 inflated, according to some embodiments of the presentinvention.

FIG. 6B1 is a partial longitudinal cross-sectional view of the expansioncatheter 620 of FIG. 6A1 along section 6B1-6B1 shown in FIG. 6A1.

FIG. 6B2 is a partial longitudinal cross-sectional view of the expansioncatheter 620 of FIG. 6A2 along section 6B2-6B2 shown in FIG. 6A2.

FIG. 6C is a side view of an expansion catheter 604 with a plurality ofballoons 673 in which the catheter shaft 121 is located on the outsideof the balloons 6730, according to some embodiments of the presentinvention.

FIG. 6D1 is a side view of an expansion catheter 640, with a singleballoon 670 in a deflated state, in which a catheter shaft 621 passesthrough the center of the balloon 670 in a neutral undeflectedconfiguration, according to some embodiments of the present invention.

FIG. 6D2 is a side view of expansion catheter 640, with single balloon670 in an inflated state and undeflected neutral configuration,according to some embodiments of the present invention.

FIG. 6D3 is a side view of expansion catheter 640, with single balloon670 in an inflated state, in which a catheter shaft 621 passes throughthe interior of the balloon 670 in a deflected configuration, accordingto some embodiments of the present invention.

FIG. 6D4 is a side view of an expansion catheter 650, with a singleballoon 680 in a deflated state, in which a catheter shaft 623 isadhered along the side of the balloon 680 in a neutral and a deflectedconfiguration, according to some embodiments of the present invention.

FIG. 6D5 is a side view of expansion catheter 650, in which cathetershaft 623 in its undeflected neutral configuration is adhered along theside of the balloon 680, which is in an inflated state, according tosome embodiments of the present invention.

FIG. 6D6 a side view of expansion catheter 650, with single balloon 680in an inflated state, in which catheter shaft 623 is in a deflectedconfiguration is adhered along the side of the balloon 680, which isaccording to some embodiments of the present invention.

DETAILED DESCRIPTION OF FIGURES

Although the following detailed description contains many specifics forthe purpose of illustration, a person of ordinary skill in the art willappreciate that many variations and alterations to the following detailsare within the scope of the invention. Specific examples are used toillustrate particular embodiments; however, the invention described inthe claims is not intended to be limited to only these examples, butrather includes the full scope of the attached claims. Accordingly, thefollowing preferred embodiments of the invention are set forth withoutany loss of generality to, and without imposing limitations upon theclaimed invention. Further, in the following detailed description of thepreferred embodiments, reference is made to the accompanying drawingsthat form a part hereof, and in which are shown by way of illustrationspecific embodiments in which the invention may be practiced. It isunderstood that other embodiments may be utilized and structural changesmay be made without departing from the scope of the present invention.The embodiments shown in the figures and described here may includefeatures that are not included in all specific embodiments. A particularembodiment may include only a subset of all of the features described,or a particular embodiment may include all of the features described.

It is specifically contemplated that the present invention includesembodiments having combinations and subcombinations of the variousembodiments and features that are individually described herein (i.e.,rather than listing every combinatorial of the elements, thisspecification includes descriptions of representative embodiments andcontemplates embodiments that include some of the features from oneembodiment combined with some of the features of another embodiment,including embodiments that include some of the features from oneembodiment combined with some of the features of embodiments describedin the patents and application publications incorporated by reference inthe present application). Further, some embodiments include fewer thanall the components described as part of any one of the embodimentsdescribed herein.

The leading digit(s) of reference numbers appearing in the figuresgenerally corresponds to the figure number in which that component isfirst introduced, such that the same reference number is used throughoutto refer to an identical component which appears in multiple figures.Signals and connections may be referred to by the same reference numberor label, and the actual meaning will be clear from its use in thecontext of the description.

Certain marks referenced herein may be common-law or registeredtrademarks of third parties affiliated or unaffiliated with theapplicant or the assignee. Use of these marks is for providing anenabling disclosure by way of example and shall not be construed tolimit the scope of the claimed subject matter to material associatedwith such marks.

FIG. 1A is an isometric view that illustrates an expansion catheter 101with balloons 170 deflated and a guidewire inserted and the expansioncatheter in its neutral state aligned along a longitudinal axis,according to some embodiments of the present invention. FIG. 1Aillustrates expansion catheter 101 in a neutral state with a guidewireinserted into its central lumen, the expansion catheter being ready forintroduction into a body opening such as a nasal passageway or throat.In some embodiments, expansion catheter 101 includes two major elements:catheter body 100 and hub 140. Guidewire 20 passes through the center ofhub 140 and catheter body 100 and exits at the distal tip of catheterbody 100. In use, flexible guide wire 20 is fed into the intended bodylumen, then the body of expansion catheter 100 is pushed into the bodylumen over the guidewire to the desired position in the body lumen, thenthe guidewire is removed (either before or after inflating theballoons), then the deflection mechanism is inserted into central lumen116 (see FIG. 2C) to the desired depth position, and locked at thatdepth by applying a desired amount of deflection and tightening a TuohyBorst lock-and-seal mechanism 138 (see FIG. 2C) of hub 140.

FIG. 1B is an isometric view that illustrates expansion-deflectioncatheter 102 with balloons 170 inflated and a deflection mechanism 300inserted and the expansion catheter curved relative to its longitudinalaxis in a neutral state, according to some embodiments of the presentinvention. FIG. 1B illustrates expansion-deflection catheter 102 withdeflection mechanism 300 inserted into expansion catheter 101 with thedeflection mechanism articulated to deflect a portion of expansioncatheter 101 from its normal longitudinal axis in its neutral state.

Referring to FIG. 1A, catheter body 100 includes tip section 110,articulating section 120 and proximal section 130, all operably coupledtogether. Hub 140 is operably coupled to catheter body 100.

Referring to FIG. 1B, articulating section 120 has at least two or moreballoons 170 (six balloons 170 are shown in this embodiment of FIG. 1B)bonded to its outer catheter surface. Metal bands 160 are interspersedbetween the balloons 170 and also distal to the most distal balloon andproximal to the most proximal balloon 170 such that each balloon 170 isdemarcated by a metal ring 160 on either side of the balloon 170 forpurposes of visualization, such as by fluoroscopy. In other embodiments,the number of balloons 170 is two, three, four, or five, while in stillother embodiments, the number of balloons 170 is in a range of seven toten inclusive, a range of ten to fifteen, inclusive, or a range ofsixteen to thirty, inclusive, or more than thirty balloons 170.

In some embodiments, sections 110, 120 and 130 include one or moreflexible plastic tube(s) forming catheter shaft 121 made from anextrusion of a thermoplastic elastomer (and if not a single piece, thenconnected end-to-end), for example, made of one or more materialsincluding but not limited to nylon, polyurethane, polyester, orpolyetheretherketone. In some embodiments, the durometer of the plastictubing 121 is in a range from 10 A to 90 D, more typically from 45 D to72 D. In some embodiments, sections 110, 120 and 130 of catheter body100 include a single durometer plastic or include one or more polymersof several durometers along the catheter shaft 121 to provide differentresponses to the action of a deflection mechanism located therein. Forexample, in some embodiments, it is helpful to have stiffer plastics forsections 110 and 130, which are not required to curve (or not requiredto curve as much), and a softer plastic for section 120, which bends inresponse to a deflection force. Alternatively, in some embodiments, itis beneficial to have a softer material at the distal end 110 of thecatheter 101 to reduce injury or trauma to a body lumen 99 (see FIG. 4Aand FIG. 4B) during insertion of an expansion catheter 101. In someembodiments, the outer diameter of catheter shaft 121 is in a range from1 to 30 Fr (0.33 to 10.0 mm) (0.013 to 0.130 inch) inclusive, and insome such embodiments, from 4 to 9 Fr (1.33 to 3.0 mm) (0.052 to 0.118inch). In some embodiments, the inner diameter of catheter shaft 121(i.e., the diameter of lumen 116) is in a range from 0.1 to 10 mm (0.004to 0.393 inch), and in some such embodiments, in a range from 0.25 to2.5 mm (0.001 to 0.098 inch). In some embodiments, and within the scopeof the current invention, that one or more diameter dimensions of thecatheter shaft 121 changes longitudinally, with one or more sectionsamong 110, 120 and 130 having different outer and/or inner diameters. Insome embodiments, the plurality of balloons 170 have two or moredifferent diameter dimensions D (see FIG. 2B) and/or length dimensionsL, such that some balloons 170 have diameters D or lengths L that aredifferent than the diameter dimensions D or length dimensions L ofothers of the plurality of balloons 170.

FIG. 2A1 is a cross-sectional view of catheter shaft 121 of expansioncatheter 101 through plane 2A1-2A1 shown in FIG. 1B, according to someembodiments of the present invention.

FIG. 2A2 is a cross-sectional view of catheter shaft 121 and balloon 170of expansion catheter 101 through plane 2A2-2A2 shown in FIG. 1B,according to some embodiments of the present invention. In someembodiments, catheter shaft 121 in section 120 includes an outer surface112, inner surface 114 defining tube wall 113. In some embodiments,contained within wall 113 are one or more oblong-oval-shaped lumens 118.In some embodiments, each lumen 118 is separated from other lumens 116and 118 and traverses the entire length of catheter body 100. At aminimum, in some embodiments, each lumen 116 and/or 118 traversescatheter body sections 120 and 130 to operably couple each lumen 116and/or 118 to the corresponding feature in hub 140. However, someembodiments incorporate lumens 116 and/or 118 joined along part of theirindividual lengths, while some other embodiments terminate some lumens116 and/or 118 along the length of the catheter body 100. In someembodiments, the lumens 116 and/or 118 serve multiple purposes, such aschannels for inflation and deflation of balloons and access means forpositioning instrumentation within a luminal space. In some embodiments,the lumens 116 and/or 118 can be used as conduits for injection orextraction of fluids from a surrounding luminal volumetric space, asthrough port 125 of FIG. 1A. In some embodiments, port 125 is operablyconnected to one of the lumens 118.

FIG. 2B is a longitudinal cross-section view of section 120 of expansioncatheter 101 along the longitudinal centerline of expansion element 170corresponding to sectional view 2B-2B of FIG. 1B. As shown in FIG. 2B,balloon 170 is attached to outer surface 112 of catheter shaft 121 atjoint 172. As shown in FIG. 2B, the balloons 170 are bulbous shaped intheir center region, from which extends a tubular section for bondingeach end of the balloon 170 to a catheter shaft 121. In someembodiments, expanded balloons 170 with this profile are made fromelastic or compliant materials. In some embodiments, balloons 170 have aspherical shape in their center region and a tubular section 172 at eachend for attaching to catheter surface 112. Alternatively, in someembodiments, balloons 170 have a cylindrical shape in their centerregion and a conical section at each end from which extends a tubularsection 172 for attaching to balloon catheter shaft 121. In someembodiments, balloons 170 with this shape are made from non-distensiblematerials. Expanded balloons are defined by a diametral dimension, D,which for a sphere or cylinder is defined as its diameter D and alength, L, defined as the shortest distance between balloon stemslocated on either end of the balloons for interfacing to outer surface112 of catheter shaft 121 as illustrated in FIG. 2B. The L/D ratio for aballoon is defined as length of a balloon, L, divided by its diameter,D, when expanded to its design diameter or pressure. For someembodiments of the current invention, the L/D ratio ranges between 0.5and 10.0, preferably between 1.0 and 5.0, and most preferably between1.0 and 3.0.

Expansion-deflection catheter devices 102 utilizing balloons 170 withsmaller L/D ratios will have better alignment of the device along thecenterline of the esophagus because of the increased number of hingepoints. This effectively translates more of the curvature of the deviceinto deflection of a body lumen 99. However, smaller L/D ratios requiremore balloons 170, which increases design complexity and manufacturingcosts.

In some embodiments, the balloons 170 are made of elastic or compliantmaterials which stretch when pressurized. Suitable materials include,but are not limited to, silicones of various durometers, latex rubbersof various durometers and lower-durometer polyurethanes and blends oflow-durometer plastic materials such as C-Flex®. In other embodiments,balloons 170 are made of non-compliant materials that have a fixed shapeand that are wrapped around a catheter shaft in their deflated state andunfold when pressurized. In some embodiments, such materials includevarious durometer nylons, polyethylene terephthalate (PET), polyestersand blends of different polymer families. In some embodiments, joints172 are bonds which form a fluid seal so that the interior space of theballoon can be pressurized for purposes of expansion and deflation ofthe balloons. Typically, such joints are formed using an adhesivesuitable for joining the materials of the balloon and catheter shaft.Examples of suitable adhesives are UV-cure adhesives such as Dymax 1161and cyanoacrylates such as Henkel 4014. Alternatively, in someembodiments, the bond is thermally formed by reflowing both the balloonand shaft materials at a temperature and pressure sufficient to causethe materials to mix and form a homogenous material. Alternatively, insome embodiments, a mechanical bond is formed using a rigid ring tocompress the balloon material against the catheter shaft material,forcing the two surfaces into intimate contact with each other,resulting in a fluid seal. In some embodiments, rings are made of, orinclude, one or more metals such as stainless steel, nitinol, nickel,copper, or any other ductile metal material. In some embodiments, ringsare made of, or include, one or more high-strength plastics, such asnylons, polyesters, polycarbonates, or PEEK. In some embodiments, hole174 is located on catheter shaft 121 within the interior space ofballoon 170. In some embodiments, hole 174 is typically a skive, whichremoves the outer surface layer from a lumen 118 to operably couple theinterior space of the balloon 170 to an underlying passageway of lumen118. In some embodiments, the interior space(s) of multiple balloons areconnected to a single lumen 118, each via an internal skive hole 174,whereby all balloons are inflated at one time, while in otherembodiments, each balloon 170 is connected to its own dedicated lumen118, allowing separate individual balloon inflations/deflations. Someembodiments use a combination of the two approaches, wherein one or moreballoons 170 are coupled to each one of a plurality of lumens 118.

FIG. 1B shows marker bands 160 placed along catheter body section 120 todemarcate each balloon for purposes of visualization (e.g., when imagedusing x-ray or fluoroscopy). In some embodiments, marker bands 160 aremade of a radiopaque material to be visible under fluoroscopy. In someembodiments, bands are made of (or include) metal such as stainlesssteel, Nitinol, nickel, copper, or any other ductile metal. In someembodiments, rings 160 are adhesively bonded to the outer surface 112 ofthe catheter shaft at joint 162 as shown in FIG. 2B. In someembodiments, the rings are mechanically crimped onto outer surface 112to form an interference fit. In some embodiments, rings used for markerbands 160 are placed over each balloon stem 172 to enhance the seal of aballoon 170 to the catheter shaft 121 outer surface 112, thus allowingmarker bands 160 to serve two functions: both as visualization indiciaand as balloon seals.

In some embodiments, one or more skive holes 174 are formed in thesurface 112 of a catheter shaft and located in any suitable catheterposition along catheter body 100. In some embodiments, one or more skiveholes 176 is/are operably coupled to the exterior environment inside thebody lumen and outside or surrounding the balloons 170, and to one ormore lumens 118 contained within catheter shaft 121. In someembodiments, one or more skive hole(s) 176 serves as a port throughwhich fluids are injected into or extracted from the luminal volumebetween two balloons and the interior surface of a body lumen. In someembodiments, each skive hole 176 and its operably coupled lumen 118 alsofunctions as a conduit through which instrumentation, such astemperature probes, are inserted into the luminal space between theballoons and the interior surface of a body lumen.

FIG. 2C illustrates one embodiment of hub 140 of FIG. 1A. At the centerof hub 140 is elongated plastic member 142 to which are operably coupledone or more side arms 145 and/or 146. In some embodiments, side arms 145and/or 146 terminate in a luer fitting for connecting to a matingfitting, such as that of a syringe. Contained within sidearm 145 isinternal lumen 143 and contained within sidearm 146 is internal lumen144. Both lumens 143 and 144 extend into and through the interior of hub142 which also contains central lumen 141. In some embodiments, thedistal end of hub 140 contains a recessed well 139 into which cathetersection 130 is inserted and adhesively bonded to form fluid seal 149.Lumens 143 and 144 are in fluid communication with one or morerespective lumens 118 and/or 118′ of catheter shaft 121. In someembodiments, attached at the proximal end of plastic member 142 is aTuohy Borst assembly 138 that includes cap 148 and gasket 147. The holein the cap 148 of the Tuohy Borst assembly 138 is in fluid communicationwith central lumen 141 of hub 140 which in turn is in fluidcommunication with central lumen 116 of catheter shaft 121. In someembodiments, sidearms 145 and 146 serve one or more of severalfunctions. In some embodiments, one of the side arms is used forinflation and deflation of the balloons attached to catheter body 100.In some embodiments, one of the side arms 145 and 146 is used to injectand extract fluids from the luminal volumetric space contained betweenthe delivery catheter and the inner wall of a body lumen such as throughport 125 of FIG. 1A. In some embodiments, the lumen 141 through theTuohy Borst assembly 138 of hub 140 is used for housing a guidewire 20during insertion of an expansion catheter 101 into a body lumen, or forhousing a deflection mechanism 300 for changing the shape of anexpansion-deflection catheter device 102.

FIG. 1A illustrates the use of a multiple balloons 170 individuallyaffixed to a catheter shaft 121, each as shown in the cross-sectionalview of FIG. 2B, to effectively center a catheter shaft 121 in a bodylumen in a straight state as shown in FIG. 1A, or in a curved state asshown in FIG. 1B.

As illustrated in FIG. 2D, the same effect can be achieved with a singleballoon that has multiple segments incorporated into the overall balloonshape. In some embodiments, for a balloon 270 that includes a compliantor semi-compliant material, marker bands 162 are used, not only asindicia for x-ray positioning of the device, but also to affix theballoon 270 as multiple inflatable segments to the catheter shaft 221,effectively creating multiple sealed spaces from one larger space. Insome embodiments, for a balloon 270 that includes semi-compliant ornon-compliant materials, the segmented geometry is fabricated into theballoon 270 during balloon formation, with the balloon stems bonded tothe shaft at the two ends and/or at each intermediate location with athermal (fusing the balloon material to catheter shaft 221 using heat),adhesive (using a compatible adhesive) and/or mechanical (using markerbands 162) bond.

FIG. 3A shows a longitudinal cross sectional view of deflectionmechanism 300. In some embodiments, deflection mechanism 300 includesfour important elements, namely:

(1) flexible section 305 which contains a number of longitudinalelements which deflect in response to action of a tensioning wire;

(2) tensioning wire 322 which moves longitudinally within column 340;

(3) column 340 which reacts to forces generated by a tensioning wire;and

(4) handle 350 which contains a knob which interfaces with column 340.

Referring to FIG. 3A, the outer shell of deflection mechanism 300includes outer tube 310 to which is affixed tip 312 at its distal endand handle assembly 350 at its proximal end. In some embodiments, thedistal section of deflection mechanism 300 is flexible and curves, whilethe proximal section is more rigid and remains relatively straight. Insome embodiments, the flexible section 305 contains leaf-spring assembly307. In some embodiments, the rigid section contains column 340 andtensioning wire 322.

In some embodiments, outer tube 310 is bonded to tip 312 on its distalend and to handle 350 on its proximal end. Outer tube 310 provides acontainer for the internal contents of deflection mechanism 300 andcontains a lubricious outer surface to aid in the insertion andpositioning within expansion catheter 101 of FIG. 1A. In one preferredembodiment, outer tube 310 is made of a lubricious material such as theTeflon® family, PTFE (polytetrafluoroethylene), ETFE (ethylenetetrafluoroethylene), or PFA (perfluoroalkoxy alkane) or from thepolyethylene family, HDPE (high-density polyethylene) or LDPE(low-density polyethylene). Alternatively, a less lubricious materialsuch as a nylon, polyester or polyurethane is used in some embodiments,and a lubricious coating applied to its outer surface using commonlyavailable deposition methods well known to one schooled in the art, suchas Applied Membrane Technology's Silglide™ coating. Outer tube 310 isbonded to distal tip 312 and handle 350 using compatible adhesives forthe materials being joined.

In some embodiments, leaf-spring assembly 307, contained within thecentral lumen of outer tube 310, includes rectangular wires 325, 330 and335 which form a composite structure which bends in a single plane whena longitudinal force is applied to its distal end and returns to itsneutral position upon release of the force. Rectangular wire 325 has alongitudinal length L₁ measured from its most proximal edge located atjunction 337 to the most proximal edge of tip 312. In some embodiments,rectangular wire 330 begins at the same proximal location 337 andextends distally along wire 325 to 327, a length L₂ where L₂ is lessthan L₁. In some embodiments, rectangular wire 335 is similarlyconfigured to begin at the same proximal location and extend distally tojoint 332—a length L₃ where L₃ is less than L₂. In some embodiments,wires 325, 330 and 335 are made of high-strength metals such as temperedstainless steel, Nitinol, and/or hardened steels or high-durometerplastics such as PEEK, nylon 6/6, polyimides, or liquid crystal polymers(LCP).

Rectangular wires are defined by a width W and a height H as shown inFIG. 3B. For some embodiments of the current invention, W is in a rangefrom 0.25 to 10 mm (0.001 to 0.39 inch) inclusive, and in some suchembodiments, W is in a range from 0.5 to 5 mm (0.020 to 0.197 inch)inclusive, or from 1.0 to 2.5 mm (0.039 to 0.098 inch) inclusive. Forsome embodiments of the current invention, H is in a range from 0.125 to5 mm (0.005 to 0.197 inch) inclusive, and in some such embodiments, H isin a range from 0.25 to 2.5 mm (0.001 to 0.098 inch) inclusive, or from0.5 to 1.25 mm (0.020 to 0.049 inch) inclusive. For some embodiments ofthe current invention, L₁ is in a range from 11.0 to 18.0 cm (4.33 to7.08 inch) inclusive, and in some such embodiments, in a range from 14.0to 16.0 cm (5.51 to 6.29 inch) inclusive. For some embodiments of thecurrent invention, L₂ is in a range from 6.0 to 11.0 cm (2.36 to 4.33inch) inclusive, and in some such embodiments, in a range from 7.0 to10.0 cm (2.76 to 3.94 inch). For the current invention, L₃ can rangefrom 3.0 to 9.0 cm (1.18 to 3.54 inch) but preferably from 4.0 to 6.0 cm(1.57 to 2.36 inch).

In some embodiments, attached to the distal end of leaf-spring assembly307 is tensioning wire 322 which is affixed to rectangular wire 325 atjoint 315. in some embodiments, the proximal end of tensioning wire 322is affixed to handle 350 at joint 348. In some embodiments, tensioningwire 322 includes a high-strength metal such as tempered stainlesssteel, Nitinol, and/or other hardened steels. For some embodiments ofthe current invention, wire diameters range from 0.05 to 1.0 mm (0.002to 0.040 inch) inclusive, preferably from 0.1 to 0.5 mm (0.004 to 0.020inch) inclusive, more preferably around 0.3 mm (0.012 inch) inclusive.In some embodiments, joint 315 includes silver solder or an adhesive.

In some embodiments, attached to the proximal end of leaf-springassembly 307 is adapter 337 which anchors the proximal end of flat wires325, 330 and 335 and also has a through hole 336 for passage oftensioning wire 322. In some embodiments, each flat wire is soldered oradhesively bonded into a well on the distal side of adapter 337.

In some embodiments, attached to the proximal side of adapter 337 iscolumn 340. In some embodiments, column 340 includes a thin-walled metaltube, such as a hypodermic tube. In some embodiments, the hypodermictube is made of high-strength metals such as hardened stainless steel,Nitinol, and/or other hardened steel alloys, or high-durometer plasticssuch as PEEK, nylon 6/6, polyimides, or liquid crystal polymers (LCP).In some embodiments, the outer diameter of hypodermic tube 340 is in arange from 0.5 to 5.0 mm (0.020 to 0.198 inch) inclusive, morepreferably from 1.0 to 2.5 mm (0.039 to 0.098 inch) inclusive. Inanother embodiment of the current invention, column 340 includes atightly wound wire coiled tube like the outer casing of a speedometercable. In some embodiments, the wire composition includes high-strengthmetals such as tempered stainless steel, Nitinol, and/or hardened steelalloys. In some embodiments, wire diameter is in a range from 0.05 to1.0 mm (0.002 to 0.039 inch) inclusive. In some embodiments, the outerdiameter of the wire coil structure is in a range from 0.5 to 5.0 mm(0.020 to 0.198 inch) inclusive, more preferably from 1.0 to 2.0 mm(0.039 to 0.078 inch) inclusive.

In some embodiments, the proximal end of column 340 is bonded to slideassembly 355. In some embodiments, slide assembly 355 includes a metaltube with external threads which mate with corresponding internalthreads contained within knob 358. In some embodiments, tensioning wire322 passes through the hole in adapter 337, through the center of column340, through slide 355, terminating in the proximal region of handle 350at joint 348. In some embodiments, locking device 360 is a threadedassembly used to fix the position of knob 358 during operation toprevent unintended changes in the curvature of deflection mechanism 300during use.

The function of deflection mechanism 300 is to laterally displace aportion of the straight line defined by connecting tip 312 and handle350 when the deflection mechanism in its neutral state, i.e., with noforce on tensioning wire 322, as shown in FIG. 3A.

In some embodiments, as force is applied to tensioning wire 322, an arcis created in spring assembly 307 defined by an axial length L_(x) and alateral displacement D_(y) as shown in FIG. 3C. This displacementresults from tensioning wire 322 causing the distance between the distaland proximal ends of rectangular wire 325 to foreshorten by virtue ofmoving a portion of rectangular wire 325 laterally, i.e., perpendicularto its longitudinal axis in its neutral state. There are severalimportant design considerations to accomplish the requisite lateraldisplacement for a given application. First, in general, the axiallength of the displaced section L_(x) is controlled by the distancebetween the location of joints 315 and 337 of FIG. 3A. As this distanceincreases, the length of the curved section correspondingly increases.For the current invention, curves can range up to 20.0 cm (7.87 inch),preferably up to 12.0 cm (4.72 inch), and more preferably from 3.0 to5.0 cm (1.18 to 1.97). Second, the lateral displacement D_(y) iscontrolled by longitudinal movement or stroke length of knob 358. Longerstroke lengths result in more lateral deflection. For the currentinvention, lateral displacements can range up to 10.0 cm (3.93 inch),preferably up to 6.0 cm (2.36 inch), and more preferably from 1.5 to 4.0cm (0.59 to 1.57 inch). Third, there is an interrelationship betweenL_(x) and D_(y): As L_(x) becomes longer, the stroke length to achievean equivalent D_(y) also becomes longer. Because stroke length isimplemented in the handle, there is a finite stroke length beyond whichthe handle length would be clinically impractical. For the currentinvention, stroke lengths can range up to less than 5.0 cm (1.96 inch),preferably up to less than to 3.0 cm (1.18 inch). Fourth, the forcerequired to move the deflection mechanism into a curve configurationdepends on the thickness of the wires used in the deflection mechanism.Using beam-bending analysis, deflection forces increase as the cube ofwire thickness, H, and linearly with wire width, W. The benefit ofthicker wire is the curvature will be more repeatable and the deflectionmechanism can withstand more force before buckling or bending sideways.This is particularly important when the forces required to deflect thebody lumen are large. Fifth, the geometry of the arc depends on therelationship between the rectangular wires used in the deflectionmechanism: As the distance L₁, L₂ and L₃ decrease, the radius ofcurvature will become smaller. If the distances L₁-L₂ and L₂-L₃ areequal, the curve will be more uniform and approximate part of a circulararc. Unequal segment lengths will change the curvature, causing aportion of the arc to have a larger radius of curvature and otherportions to have a smaller radius. Such shapes may be advantageous toprovide non-circular arcs for the purpose of navigating tortuouspathways or deflecting around multiple body structures.

FIG. 3A is a longitudinal cross-sectional view of a deflection mechanism300 for insertion into an expansion catheter, according to someembodiments of the present invention. FIG. 3A shows an embodiment of thedeflection mechanism of the current invention using three wires, eachwire having a similar cross section defined by its width, W, and height,H and lengths L₁, L₂ and L₃. Other embodiments are possible within thescope of the current invention to accomplish the same mechanicaldeflection as the illustrated device. One such example is the use ofmore wires of similar cross section each having a different length.Assemblies containing 2, 3, 4, 5, 6 or up to 20 wires fall within thescope of the present invention. In some embodiments, individual wireswith different widths W and heights H are combined within one leafspring assembly. Because the use of more wires comes with attendantincrease in manufacturing difficulty, in some embodiments of the currentinvention a single wire with a larger height H is used with alongitudinal cross-sectional profile which changes between theequivalent points defined by L₁ and L₃. In some embodiments, such ashape is mechanically ground or chemically etched into its heightprofile within the distal region corresponding to the section defined byL₁ thru L₃. In some embodiments of the current invention a single wirewith width W is used with a longitudinal cross-sectional profile whichchanges between the equivalent points defined by L₁ and L₃. Thelongitudinal profiles may be such that they vary continuously along thelongitudinal length or may have multiple discrete changes in which agiven section has a uniform profile for a defined distance less than thetotal distance between L₁ to L₃. In some embodiments of the currentinvention a combination of wires with a uniform cross sectionallongitudinal profile is combined with ones with a variable longitudinalprofile. In some embodiments, such inner assembly designs are used tochange the shape of the arc used to deflect the catheter to obtain thedesired deflection curvature.

The deflection mechanism of FIG. 3A shows a device in which lateraldisplacement occurs within a single arc in one plane. In someembodiments of the current invention, a deflection mechanism based onthe same principles of operation is designed such that displacementoccurs in different geometric arc configurations and occurs in multipleplanes. For example, in some embodiments of the current invention adeflection mechanism has two different radii of curvature but stilloccurs within the same plane. Such a design involves adding a secondtensioning wire with a contact point proximate to 315 with thetensioning wire interfacing with a second knob on handle 350 similar tothat of tensioning wire 322 with knob 358. Another embodiment includes adeflection mechanism in which the lateral deflection occurs in twodifferent planes. Such a design is possible by making one or more wires325, 335 and 340 more square, W/H ratio closer to 1 and adding a secondtensioning wire with a joint on a wire face 90 degrees to the face ofthe wire that contains joint 315, and interfacing this second tensioningwire with a second knob on handle 350 similar to that of tensioning wire322 with knob 358.

In one embodiment of the current invention, deflection mechanism 300 andexpansion catheter 101 of FIG. 1A are separate entities which areoperably combined by inserting deflection mechanism 300 into a lumen ofexpansion catheter 5. Expansion catheter 101 is designed such thatlateral displacement of deflection mechanism 300 results in acorresponding lateral displacement of at least a portion of catheterbody 100 of expansion catheter 101. The location of the deflectionsection and rotation of the deflected section relative to the TuohyBorst hub 140 can be changed by slideably moving and/or rotatingdeflection mechanism 300 within expansion catheter 101.

In another embodiment of the current invention, a passive stylet is usedto shape the deflection device 10. In such embodiments using passivestylets, the curved stylet is used similarly to deflection mechanism 300to curve a section of expansion catheter 5.

FIG. 3D shows the distal end of stylet 360 made of wire 365 shaped witha single deflection curve for insertion into deflection catheter 101.The wire can be made from stainless steel, Nitinol, or any high-strengthmetal which when shaped can provide the requisite force to deflect abody organ. In various embodiments of the present invention, wire sizesrange from 0.1 to 2.0 mm (0.004 to 0.079 inch).

FIG. 3E illustrates a geometry which is not a segment of a circular arc.FIG. 3F illustrates a geometry which contains a compound curvature thatlies in a single plane. FIG. 3G illustrates a geometry in which thecompound curvature lies in two different planes.

In another embodiment of the current invention, junction 315 islaterally displaced from tip 312 to provide a section distal to junction315 which is not deflected. This may be advantageous in certainapplications to provide a more uniform transition between the end of thedeflected section of an expansion catheter and its distal non-deflectedsection. The greater the distance between junction 315 and tip 312, thelonger the transition region.

In another embodiment of the current invention, deflection mechanism 300and balloon center catheter body 100 are designed as a single combinedintegral unit forming expansion-deflection catheter device 308. One mainadvantage of this design is fewer parts/materials, with a correspondingreduction in overall device diameter. The location of the deflectedsection and rotation of the deflected section relative to the TuohyBorst hub 140 of expansion catheter 101 is fixed and not changeableduring use.

One embodiment of an integral unit of the current invention is shown inFIG. 3H, in which the deflection mechanism is integral to the expansioncatheter. In this embodiment, tension wire 322 passes through lumen 118of catheter body 112 and is anchored at the distal end of the deflectionzone 120 of expansion catheter 101 at junction 392. In some embodiments,metal support ring 390 is used to reinforce the junction 390 todistribute the forces in tension wire 322 over a larger surface area. Atthe proximal end of deflection zone 320, support 337 is bonded tocatheter shaft 112 and column 340 to provide the pivot point forproximal defection of the expansion catheter. Balloons 170 and rings 160are attached to catheter shaft 112 as previously described.

In operation for a preferred embodiment of the current invent usingseparate expansion and deflection elements, expansion catheter 101 isprepared for insertion into a body cavity by flushing its central lumenwith a biocompatible fluid such as physiological saline. A guidewire,preferably one with a diameter of 0.089 mm (0.035 inch), is insertedinto a body orifice and then into the intervening body passageways sothat the distal tip of the guidewire is placed distal to the regionwhere expansion catheter 101 will reside in a body lumen. For example,for esophageal deflection, the tip of the guidewire is positioned nearthe entrance to the stomach, i.e., above the pyloric sphincter. If usedin a procedure, the guidewire is then back-loaded through catheter tip115, through lumen 116 exiting at the proximal end through Tuohy Borstcap 148. Use of a guidewire is typically more important for narrow andtortuous passageways such as those through the nasal cavity when usedfor the purpose of esophageal deflection. Expansion catheter 101 is theninserted into a body orifice and threaded through the interveningpassageway until it is positioned at the desired location. For example,in an esophageal application, the tip of the expansion catheter 115 isinserted through the mouth and into the throat and then into theesophagus. The tip is then positioned near the lower part of theesophagus in a region above the pyloric sphincter. In some embodiments,the position of the catheter is evaluated using fluoroscopy and rings160 positioned on expansion catheter 5. In some embodiments, to furtherenhance imaging a fluid media such as a radiopaque salt diluted withphysiological saline is injected through one of the hub ports to inflateballoons 170. At minimum, once expansion catheter 101 is positioned,each balloon is inflated via an inflation port on the hub such that theoutside surface of the balloon is in contact with the interior walls ofa body lumen, which effectively fixes the position of the expansioncatheter 101 within the body lumen along its centerline. In someembodiments, the degree of balloon Inflation and positioning isrechecked using fluoroscopy. The guidewire is then removed fromexpansion catheter 101 and deflection mechanism 300 inserted intoexpansion catheter 101 via Tuohy Borst 148 traversing central lumen 116of catheter body 100 forming deflection device 10. Deflection mechanism300 is positioned within balloon deflection device 102 so that thesection of the deflection mechanism which curves is aligned with section120 of the expansion catheter body 100. Once proper alignment isobtained, the position of the deflection mechanism is fixed bytightening cap 148 on the Tuohy Borst assembly 138 of hub 140. In someembodiments, deflection of the catheter is accomplished by rotating knob358 of handle 350 until the desired lateral displacement of deflectiondevice 102 is attained, at which point the position of knob 358 can belocked using screw 360. In some embodiments, confirmation of thelocation, degree and plane of deflection relative to critical anatomicalstructures is assessed using fluoroscopy. For example, in the use of thecurrent invention for esophageal deflection, the position of theesophagus relative the left atrium is evaluated. The location, degreeand plane of deflection can be changed by adjusting the position ofdeflection mechanism 300 relative to deflection device 102. At thecompletion of a procedure, the deflection mechanism is returned to itsneutral position and then removed from the deflection device. Allballoons 170 are deflated and the expansion catheter 101 removed fromthe body lumen 99.

One major benefit of using the current invention is the ability tomaintain the circularity of a body lumen in the region of deflection.The ability of a device to maintain circularity can be evaluated bydefining a cross-sectional profile of a body lumen in a region away fromthe deflected section to that of a cross-sectional profile in the regionof deflection and comparing the two profiles. Referencing FIG. 4A, thiswould correspond to sectional views 4A₁-4A₁ and 4A₂-4A₂, respectively.For each cross-sectional profile, the largest distance, D, between anytwo diametrically opposite interior surfaces is measured. Referring toFIG. 4A, the values would be D_(n) for a cross-sectional profile awayfrom the deflected region and D_(d) for the cross section in thedeflected region. The values for these two measurements are thencompared. For devices which maintain circularity of a deflected lumen,these two values will be nearly identical.

FIG. 4A illustrates a body lumen which has been moved laterally using adeflection device of the current invention which maintains thecircularity of the body lumen. On the other hand, FIG. 4B illustrateslateral movement using a deflection device that includes a flexible tubewith an integral deflection device in which the outer diameter of thedevice is smaller than that of the body lumen into which it is inserted.In FIG. 4A, because deflection is accomplished using the currentinvention, the circularity of the body lumen is approximately preservedduring deflection, as indicated by comparable values for D_(n) andD_(d). However, referring to FIG. 4B, because there is significantinitial stretching of the body lumen during deflection, the profile ismore elliptical in the deflected region, resulting in D_(d) being muchlarger than D_(n).

Another measure of the benefit of using the current invention is tocalculate the translational efficacy of a deflection device. Thisparameter characterizes the ability to translate lateral displacement ofa device into corresponding movement of a body lumen. This analysismeasures the deflection of diametrically opposite points of a crosssection of a body lumen from its original or non-deflected position. Areference line for the original position of a body lumen is defined bydrawing a line connecting the outside edge of the body lumen above andbelow the deflected section. This is done for two diametrically oppositepoints on the body lumen. Referring to FIG. 4A, this defines lines 410for one edge and line 420 for the diametrically opposite edge. For FIG.4B, the corresponding designations are 410′ and 420′. Using these twodefined reference lines, the maximum deflected distance for each edge ofthe body lumen is measured from its corresponding reference line as theperpendicular distance from the reference line to the point of maximumdeflection for the same point on the body lumen. For FIG. 4A, thiscorresponds to distances D₁ and D₂ and for FIG. 4B, distances D₁′ andD₂′. Using this nomenclature, a translational efficacy can be defined as{1−(D₂−D₁)/[(D₂+D₁)/2]} for FIG. 4A and {1−(D₂′−D₁′)/[(D₂′+D₁′)/2]} forFIG. 4B. For a translation efficacy of 1.0, all motion of the devicewould be transferred into a corresponding movement of the centerline ofthe body lumen.

Referring to FIG. 4A, for a deflected section in which the cross sectionof the body lumen is not deformed, D₁ and D₂ are nearly equal and thetranslational efficacy is close to 1.0. However, for FIG. 4B, wherethere is significant deformation of the cross section of the body lumenin the deflected section, D₂ is much larger than D₁ yielding atranslational efficacy that approaches zero or, in the worst case, evenless than zero. For the current invention, the translational efficacy ispreferably greater than 0.5, more preferably greater than 0.75, and mostpreferably greater than 0.85.

Some embodiments of the current invention use other expansion means forlocating expansion catheter 101 within a body lumen. In someembodiments, other means include but are not limited to nitinol wires inthe form of a spline or a braided mesh in the form of a sphere. Suchmeans would be activated from a collapsed state with a diameterapproximately that of expansion catheter 101 to that of a body lumen bymoving the two ends of each entity towards each other either bytensioning or pushing one end. It is also envisioned within the scope ofthe current invention that balloons and expandable wire means could beused in combination with each other to form the expansion means forexpansion catheter 101.

FIG. 5A is a side view of a deflection device 520 using a pre-shapedwire spline as an expandable element, according to some embodiments ofthe present invention. FIG. 5A illustrates deflection device 520 thatuses a wire spline as an expandable element. In this embodiment,multiple formed wires 576 are attached to metal rings 562 on each end toform spline assembly 565. Multiple spline assemblies are linked togetherby attaching the distal end of one spline assembly to the proximal endof the next spline assembly via ring 562. The most proximal splineassembly has tube 570 as its most proximal ring. This tube is used toexpand and collapse individual splines. The linked spline assemblies aremounted over a center tube 560 which is affixed at 576 at its distal endto the most distal ring of the spline assembly. By pushing tube 570distally towards the tip, the spline assemblies are expanded, whilepulling tube 570 away from the tip collapses the spline assemblies.

FIG. 5B is a side view of a deflection device 530 using a single balloon571 that is helically wrapped with a metal strap 561, and in theinflated state, according to some embodiments of the present invention.In some embodiments, a single balloon 571 is used to completely coverthe outside of a catheter shaft 582. The balloon 571 is then affixed tocatheter shaft 582 in a spiral pattern using a strap 561 (e.g., made ofmetal or other material) wrapped helically around the balloon 571 andshaft 582, or by adhesive applied to the catheter shaft in a helicalpattern (not shown, but where the adhesive functions to replace strap561), or by thermally bonding the balloon to the catheter shaft 582 in ahelical pattern.

FIG. 6A1 is a side view of an expansion catheter 620 using a singleballoon 671 wrapped in a spiral pattern around a catheter shaft, shownwith balloon 671 deflated, according to some embodiments of the presentinvention.

FIG. 6A2 is a side view of an expansion catheter 620 using a singleballoon 671 wrapped in a spiral pattern around a catheter shaft, shownwith balloon 671 inflated, according to some embodiments of the presentinvention. FIG. 6A1 and FIG. 6A2 illustrate an embodiment of the currentinvention in which a single balloon is wrapped in a spiral patternaround a catheter shaft. Balloon 671 has a very high L/D ratio comparedto the balloons used in FIG. 2A and FIG. 2B. In this embodiment of thepresent invention, diameters can range from 1.0 to 20.0 mm (0.040 to0.800 inch), preferably from 3.0 to 8.0 mm (0.118 to 0.320 inch).Balloons can be made of elastic materials such as a soft-durometerpolyurethane or silicone. Balloons can also be made of non-compliantmaterials which have a fixed shape. Typical materials include variousdurometer nylons, polyethylene terephthalates (PET), polyesters andblends of different polymer families. In some embodiments, the ballooncan be thin-walled tubing with a wall thickness ranging from 0.001 to0.2 mm (0.0004 to 0.008 inch). Depending on the length of the deflectionsection, the number of spirals the balloon makes around the cathetershaft may vary from more than one (1) spiral to more than thirty (30)spirals, but preferably of the order of ten (10) spirals (or, in otherembodiments, about 5, about 15, about 20 or about 25 spirals). Usingthese ranges, in some embodiments, the L/D ratio of the balloon can varyfrom a minimum of approximately five (5) to maximum of approximately onehundred or one-hundred fifty or even up to one thousand (1,000) or more.

One difficulty in implementing this concept is a tendency for theballoon to migrate along the length of the catheter shaft and notmaintain a uniform threaded screw geometry longitudinally along thecatheter shaft. This tendency is more apparent during insertion into abody lumen where there is likely drag along the outer surfaces of thedeflated balloon. In order to overcome this tendency, grooves can belocated in the catheter shaft to house the deflated balloon.

FIG. 6B1 is a partial longitudinal cross-sectional view of the expansioncatheter 620 of FIG. 6A1 along section 6B1-6B1 shown in FIG. 6A1,wherein balloon 671 is in the deflated state.

FIG. 6B2 is a partial longitudinal cross-sectional view of the expansioncatheter 620 of FIG. 6A2 along section 6B2-6B2 shown in FIG. 6A2,wherein balloon 671 is in the inflated state. In some embodiments,helical groove 686 is embossed or imprinted in the outside of cathetershaft 612. Deflated balloon 671 is contained either partially or fully(as shown) within the confines of the groove.

Another embodiment of the present invention is shown in FIG. 6C.Balloons 170 are attached to catheter surface 112 such that the cathetershaft passes along the outside surface of balloons 170. When theballoons are expanded, catheter shaft 112 is pushed against a side of abody lumen, achieving the aforementioned effect of fixing therelationship between a catheter shaft and an expanded body lumen. Onedisadvantage to this embodiment is the expansion means must be releasedand returned to its natural position in order to repositioned theexpansion catheter.

FIG. 6D1 is a side-view of an expansion catheter 640, with a singleballoon 670 in a deflated state, in which a catheter shaft 621 passesthrough the center of the balloon 670 in a neutral undeflectedconfiguration, according to some embodiments of the present invention.

FIG. 6D2 is a side-view of expansion catheter 640, with single balloon670 in an inflated state and undeflected neutral configuration,according to some embodiments of the present invention.

FIG. 6D3 is a side-view of expansion catheter 640, with single balloon670 in an inflated state, in which a catheter shaft 621 passes throughthe interior of the balloon 670 in a deflected configuration, accordingto some embodiments of the present invention.

The embodiment of the present invention shown in FIG. 6D1, FIG. 6D2 andFIG. 6D3, includes a single balloon shown in deflated state with nodeflection in FIG. 6D1, in an expanded state with no deflection in FIG.6D2 and an expanded state with deflection in FIG. 6D3. A single balloon670 is joined to catheter shaft 67 112 at joints 172 such that thecatheter shaft passes through the interior of balloon 170. FIG. 6D1shows the balloon in a deflated state. FIG. 6D2 shows the balloon in anexpanded state to engage a body lumen. FIG. 6D3 shows the catheter shaftdeflected by a mechanical means such that the catheter shaft moves tothe outside of the deflected curve and rests against the concaveinterior surface of a body lumen fixing the relationship between acatheter shaft and an expanded body lumen and displacing the body lumenlaterally resulting in the catheter being curved from its neutral state.

FIG. 6D4 is a side-view of an expansion catheter 650, with a singleballoon 680 in a deflated state, in which a catheter shaft 623 isadhered along the side of the balloon 680 in a neutral and a deflectedconfiguration, according to some embodiments of the present invention.

FIG. 6D5 is a side-view of expansion catheter 650, in which cathetershaft 623 in its undeflected neutral configuration is adhered along theside of the balloon 680, which is in an inflated state, according tosome embodiments of the present invention.

FIG. 6D6 illustrates expansion catheter 650, with single balloon 680 inan inflated state, in which catheter shaft 623 is in a deflectedconfiguration is adhered along the side of the balloon 680, which isaccording to some embodiments of the present invention.

The embodiment of the present invention shown in FIG. 6D4, FIG. 6D5 andFIG. 6D6 includes a single balloon shown in deflated state with nodeflection, in an expanded state with no deflection and an expandedstate with deflection. A single balloon 170 is joined to catheter outersurface 112 of catheter shaft 121 at joints 172 such that the cathetershaft passes along the outside of balloon 170. FIG. 6D4 shows theballoon in a deflated state. FIG. 6D5 shows the balloon in an expandedstate to engage a body lumen. FIG. 6D6 shows the catheter shaftdeflected by a mechanical means such the body lumen is displacedlaterally resulting in the catheter being curved from its neutral state.

In one embodiment of the current invention, an expansion catheterincludes an outer tube into which is placed an inner tube to simulate amulti-lumen tube. The outer tube is an extruded nylon, such as Pebax™7233, with an outer diameter of 3.17 mm (0.125 inch), an inner diameterof 2.51 mm (0.100 inch), and a calculated wall thickness of 0.33 mm(0.013 inches). The inner tube is an extruded nylon, such as Pebax™7233, with an outer diameter of 2.33 mm OD (0.092 inch), an innerdiameter of 1.90 mm ID (0.075 inch), and a calculated wall thickness of0.22 mm (0.008 inch). The inner tube slips inside the outer tube with aclearance between the two tubes of 0.09 mm (0.0035 inch). The two tubesare bonded at their distal ends with an adhesive, Loctite™ 4014,operably sealing the annular gap. The inner tube also has a lubriciouscoating on its inside surface to facilitate insertion of a guidewire anddeflection mechanism during operation.

In one embodiment of the present invention, the expansion catheterincludes fives balloons bonded to the outer tube using Dymax UV Adhesive1161-M. Each balloon is made of soft polyurethane which can be expandedup to a working diameter of 2.54 cm (1.00 inch). The balloons are 5.0 cm(1.96 inch) long including necks. In the bonded area, the outer diameterof the bond is 3.8 mm (0.150 inches). The length of the deflectedsection—the distance from the distal edge of the most distal balloon tothe proximal edge of the most proximal balloon—is 25.4 cm (10.0 inch). Askive in the outer shaft is located within each balloon to connect theinterior of the balloon with the annular gap in the catheter shaftbetween the inner and outer tube. This configuration has a single lumenconnecting all balloons so that the balloons are inflated/deflatedsimultaneously.

In one embodiment of the current invention, the proximal end of theexpansion catheter contains a Y adapter with a single side arm having afemale luer connector and Tuohy Borst gasket with a threaded cap. The Yadapter is bonded to both the inner and outer tube of the catheter shaftto operably couple the annular channel to the side arm of the Y adapter.The Tuohy Borst functions as an entrance to the central lumen of theexpansion catheter for slideably accommodating a guidewire and adeflection mechanism and as a fixation device for locking the positionof the deflection mechanism within the expansion catheter duringoperation.

In one embodiment of the present invention, a deflection mechanismincludes a column made from a hypodermic tube with an outer diameter of1.83 mm (0.072 inch), an inner diameter of 1.6 mm (0.063 inch), and alength of 25.4 cm (10 inch). An adapter which interfaces with thehypodermic tube and the leaf-spring assembly contains three drilledholes, two of which are adjacent to each other with a third centeredbelow these two holes. The overall diameter of the adapter is 1.88 mm(0.074 inch).

In one embodiment of the current invention, two round wires are used toform a leaf spring. Each wire is made of Nitinol with a diameter of 0.81mm (0.032 inch) a length of 17 mm (6.7 inch). The Nitinol wires aresoldered into the adapter with a suitable flux and solder. An adaptersimilar to the one described above but with two holes is soldered ontothe distal end of the longer Nitinol wire.

In one embodiment of the current invention, a tensioning wire used forthe curving of the leaf spring is made from a braided stainless steelwire with an outer diameter of 0.32 mm (0.013 inch). The distal end ofthe wire is soldered into the distal adapter at the end of the longerNitinol wire. The wire is then passed thru the proximal adapter andsoldered into a small heavy wall hypodermic tube which is then fixatedwithin the handle.

In one embodiment of the current invention, a handle includes a nut anda threaded rod to move the tensioning wire longitudinally. The threadedrod is configured so that it cannot rotate but can move laterally due toa slot in the threaded rod that contains a set screw that fits into thehandle. The set-screw is loose enough to allow axial movement butprevent rotation.

In one embodiment of the current invention, with the deflectionmechanism in its neutral or straight state, deflection occurs byrotating the knob in the handle in a specific direction, causing thethreaded rod to advance distally toward the tip of the deflectionmechanism. This simultaneously advances the column connected to thethreaded rod. Because the tensioning wire is anchored at the distal endof the leaf-spring assembly and the back of the handle, the distancebetween the endpoints of the leaf-spring assembly is operably shortened,causing the leaf-spring assembly to deflect in its structurally mostflexible plane. Reversing the direction of rotation of the knoblengthens the distance between the endpoints of the leaf-springassembly, allowing the assembly to return to a more neutral state andultimately to its resting state.

In one embodiment of the current invention, a deflection, D_(y), ofapproximately 5 cm is obtained over a distance L_(x) of approximately 24cm.

In some embodiments, the present invention provides a deflectioncatheter for displacing a portion of an internal passageway of a bodylumen. This deflection catheter includes: a catheter shaft having adistal end and proximal end containing at least one lumen therein overat least a portion of length of said catheter shaft; an expandable setof balloon members affixed to the catheter shaft along at least aportion of said catheter shaft; each balloon member sealably affixed tothe catheter shaft on both its distal and proximal ends such that theinterior space of each balloon is operably coupled to at least one lumenwithin said catheter shaft; and a deflection mechanism contained withinat least one lumen of said catheter shaft and operably coupled to saidcatheter shaft, such that a change in shape of the deflection mechanismcauses a corresponding change in shape of said catheter shaft along atleast a portion of said catheter shaft which contains at least oneballoon.

In some embodiments, the present invention provides a deflectioncatheter for displacing a portion of an internal passageway of a bodylumen. This deflection catheter includes: a catheter shaft having adistal end and proximal end containing at least a first lumen thereinover at least a portion of length of said catheter shaft; one or moreexpandable members affixed to the catheter shaft along at least aportion of said catheter shaft; each expandable member sealed to thecatheter shaft on both a distal end of the expandable member and aproximal end of the expandable member such that an interior space ofeach balloon is operably coupled to first lumen within said cathetershaft; and a deflection mechanism contained within at least one lumen ofsaid catheter shaft and operably coupled to said catheter shaft, suchthat a change in shape of the deflection mechanism causes acorresponding change in shape of said catheter shaft along at least aportion of said catheter shaft which contains at least one balloon.

In some embodiments, the one or more expandable members comprises aplurality of at least five balloons spaced along a length of thecatheter shaft, the deflection mechanism is removably insertable into asecond lumen in the catheter shaft, the deflection mechanism includes adeflection portion between a proximal end and a distal end of thedeflection mechanism, the deflection portion changes a radius ofcurvature in a deflection plane upon application of a axial force on thedeflection mechanism, and the deflection mechanism includes a TuohyBorst clamping mechanism operable to lock the deflection mechanism at aselected angle of a plurality of available angles in order to set anorientation of the deflection plane's direction (i.e., the directiontoward which the expandable diverter will move the target lumen).

In some embodiments, the present invention provides an apparatus fordisplacing a portion of a body lumen. This apparatus includes: a shaft;a first lumen within the shaft extending over at least a portion oflength of the apparatus; an expandable member attached to the shaft andconfigured to expand within the body lumen; and a deflection mechanismlocated within the first lumen and configured to change shape by lateraldeflection to cause a corresponding lateral deflection of the shaftalong at least a portion of the shaft attached to the expandable member.

In some embodiments, the shape change by lateral deflection is a resultof a change in a radius of curvature of the deflection mechanism. Insome embodiments, the shape change by lateral deflection is caused byapplying tension to a portion of the deflection mechanism

Some embodiments further include a tube operatively coupled to theexpandable member to inject a fluid into the expandable member to causethe expandable member to expand within the body lumen.

Some embodiments further include a second lumen within the shaft that isoperatively coupled to the expandable member to inject a fluid into theexpandable member to cause the expandable member to expand within thebody lumen.

In some embodiments, the first lumen within the shaft is operativelycoupled to the expandable member to inject a fluid into the expandablemember to cause the expandable member to expand within the body lumen.

In some embodiments, the expandable member includes a plurality ofexpandable segments serially located along the shaft, wherein each oneof the plurality of expandable segments surrounds the shaft such thatwhen each one of the plurality of expandable segments of the expandablemember expands within the body lumen, the shaft is substantiallycentered within each one of the plurality of expandable segments.

In some embodiments, the deflection mechanism includes a plurality offlat side-by-side metal segments of different lengths and a contractioncable configured to cause a curve in the plurality of flat side-by-sidemetal segments when the cable is placed in tension.

In some embodiments, the present invention provides a positioning deviceconfigured for introduction within a body lumen. This positioning deviceincludes: a catheter shaft that has a longitudinal axis; an expandableelement coupled along a length of the shaft, the expandable elementbeing substantially flaccid in an unexpanded state and having a limitedmaximum diameter in an expanded state; and a deflection mechanismlocated within the shaft, wherein the deflection mechanism is flexiblewhen in a non-deflected state and wherein the deflection mechanismcurves in a predetermined lateral direction when in a deflected statesuch that the positioning device laterally deflects the body lumen.

In some embodiments, the present invention provides a method fordisplacing a portion of a body lumen. This lumen-displacement methodincludes: providing a shaft having a first lumen within the shaft, thelumen extending through at least a portion of length of the shaft, anexpandable member attached to the shaft, and a deflection mechanismwithin the first lumen; inserting the shaft into a body lumen of ananimal; expanding the expandable member within the body lumen of theanimal; and changing a shape of the deflection mechanism by lateraldeflection to cause a corresponding lateral deflection of the body lumenof the animal. In some embodiments, the animal is a human.

In some embodiments, the present invention provides an apparatus fordisplacing a portion of a flexible target lumen. This apparatusincludes: a catheter shaft having a first catheter-shaft lumen withinthe catheter shaft, the first catheter-shaft lumen extending through atleast a portion of length of the catheter shaft; a plurality ofinflatable and deflatable balloons located along the catheter shaft andoperably coupled to the first catheter-shaft lumen and configured toexpand in diameter within the flexible target lumen to form an expandedfirst portion of the apparatus; and a lateral deflection mechanismoperably coupled to the catheter shaft and configured to laterallydeflect the expanded first portion of the apparatus while within theflexible target lumen in order to laterally deflect the flexible targetlumen.

Some embodiments further include a guidewire to guide at least a portionof the catheter shaft into the flexible target lumen.

Some embodiments further include a guidewire to guide at least a portionof the catheter shaft into the flexible target lumen; and a secondcatheter-shaft lumen in the catheter shaft, wherein the guidewire isremovably insertable into the catheter-shaft second lumen, and whereinthe lateral deflection mechanism is removably insertable into the secondcatheter-shaft lumen.

Some embodiments further include a second catheter-shaft lumen in thecatheter shaft, wherein the guidewire is removably insertable into thecatheter-shaft second lumen, and wherein the lateral deflectionmechanism is removably insertable into the second catheter-shaft lumen.

In some embodiments, the present invention provides an apparatus fordisplacing a portion of a flexible target lumen. This apparatusincludes: a catheter shaft having a first catheter-shaft lumen withinthe catheter shaft, the first catheter-shaft lumen extending through atleast a portion of length of the catheter shaft; means for expanding adiameter of a first portion of the apparatus when the apparatus is, atleast partially, within the flexible target lumen, wherein the means forexpanding the diameter of the first portion of the apparatus is operablycoupled to the first catheter-shaft lumen; and means for laterallydeflecting the expanded first portion of the apparatus while within theflexible target lumen in order to deflect the flexible target lumen.Some embodiments further include means for guiding at least a portion ofthe catheter shaft into the flexible target lumen. Some embodimentsfurther include means for guiding at least a portion of the cathetershaft into the flexible target lumen; and a second catheter-shaft lumenin the catheter shaft, wherein the means for guiding is removablyinsertable into the catheter-shaft second lumen, and wherein the meansfor laterally deflecting the expanded portion of the apparatus withinthe flexible target lumen is removably insertable into the secondcatheter-shaft lumen. Some embodiments further include a secondcatheter-shaft lumen in the catheter shaft, wherein the means forlaterally deflecting the expanded portion of the apparatus within theflexible target lumen is removably insertable into the secondcatheter-shaft lumen.

In some embodiments, the present invention provides an apparatus fordisplacing a portion of a body lumen. This apparatus includes a shaft; afirst lumen within the shaft extending over at least a portion of lengthof the apparatus; an expandable member attached to the shaft andconfigured to expand within the body lumen; and a deflection mechanismlocated within the first lumen and configured to change shape by lateraldeflection to cause a corresponding lateral deflection of the shaftalong at least a portion of the shaft attached to the expandable member.

In some embodiments, the present invention provides an apparatus fordisplacing a portion of a body lumen. This apparatus includes: a shaft;a first lumen within the shaft extending over at least a portion oflength of the apparatus; an expandable member attached to the shaft andconfigured to expand within the body lumen; and a deflection mechanismlocated within the first lumen and configured to change shape by lateraldeflection to cause a corresponding lateral deflection of the bodylumen. Some embodiments further include a tube operatively coupled tothe expandable member to inject a fluid into the expandable member tocause the expandable member to expand within the body lumen. Someembodiments further include a second lumen within the shaft andoperatively coupled to the expandable member to inject a fluid into theexpandable member to cause the expandable member to expand within thebody lumen. In some embodiments, the first lumen within the shaft isoperatively coupled to the expandable member to inject a fluid into theexpandable member to cause the expandable member to expand within thebody lumen. In some embodiments, the expandable member includes aplurality of expandable segments serially located along the shaft,wherein each one of the plurality of expandable segments surrounds theshaft such that when each one of the plurality of expandable segments ofthe expandable member expands within the body lumen, the shaft issubstantially centered within each one of the plurality of expandablesegments. In some embodiments, the deflection mechanism includes aplurality of flat side-by-side metal segments of different lengths and acontraction cable configured to cause a curve in the plurality of flatside-by-side metal segments when the cable is placed in tension.

In some embodiments, the present invention provides a positioning deviceconfigured for introduction within a body lumen. This device includes: ashaft with a longitudinal axis; an expandable element coupled along alength of the shaft, the expandable element being substantially flexibleand thin in an unexpanded state, and exerting a gentle outward force inan expanded state; and a deflection mechanism located within the shaft,wherein the deflection mechanism is flexible when in a non-deflectedstate and wherein the deflection mechanism curves in a predeterminedlateral direction when in a deflected state such that the positioningdevice laterally deflects the body lumen.

In some embodiments, the present invention provides a method fordisplacing a portion of a body lumen, the method including: providing ashaft having a first lumen within the shaft, the lumen extending throughat least a portion of length of the shaft, an expandable member attachedto the shaft, and a deflection mechanism within the first lumen;inserting the shaft into a body lumen of an animal; expanding theexpandable member within the body lumen of the animal; changing a shapeof the deflection mechanism by lateral deflection to cause acorresponding lateral deflection of the body lumen of the animal. Insome embodiments, the animal is a human. In some embodiments, thedeflection mechanism is inserted into the first lumen after the shafthas been inserted into the body lumen of the animal.

It is to be understood that the above description is intended to beillustrative, and not restrictive. Although numerous characteristics andadvantages of various embodiments as described herein have been setforth in the foregoing description, together with details of thestructure and function of various embodiments, many other embodimentsand changes to details will be apparent to those of skill in the artupon reviewing the above description. The scope of the invention should,therefore, be determined with reference to the appended claims, alongwith the full scope of equivalents to which such claims are entitled. Inthe appended claims, the terms “including” and “in which” are used asthe plain-English equivalents of the respective terms “comprising” and“wherein,” respectively. Moreover, the terms “first,” “second,” and“third,” etc., are used merely as labels, and are not intended to imposenumerical requirements on their objects.

What is claimed is:
 1. A method for displacing a portion of a body lumen, the method comprising: providing: a shaft having a first lumen within the shaft, wherein the first lumen extends through at least a portion of a length of the shaft, an expandable member attached to the shaft, and a deflection mechanism operably coupled to the shaft; inserting the shaft into a body lumen of an animal; expanding the expandable member within the body lumen of the animal; changing a shape of the deflection mechanism by lateral deflection to form a deflected portion of the shaft and cause a corresponding lateral deflection of the body lumen of the animal, wherein at least a portion of the expandable member surrounds at least a part of the deflected portion of the shaft; and rotating the deflection mechanism circumferentially within the first lumen to a desired circumferential location.
 2. The method of claim 1, wherein the expanding of the expandable member includes injecting a fluid into the expandable member.
 3. The method of claim 1, wherein the shaft includes a second lumen within the shaft, and wherein the expanding of the expandable member includes injecting a fluid into the expandable member via the second lumen.
 4. The method of claim 1, wherein the expandable member includes a plurality of expandable segments serially located along the shaft, wherein each one of the plurality of expandable segments surrounds the shaft such that when each one of the plurality of expandable segments of the expandable member expands within the body lumen, the shaft is substantially centered within each one of the plurality of expandable segments.
 5. The method of claim 1, further comprising: evaluating a degree and plane of curvature of the deflection mechanism using an imaging modality.
 6. The method of claim 1, wherein the changing of the shape of the deflection mechanism includes maintaining a translational efficacy of the deflection mechanism at a value greater than 0.85.
 7. The method of claim 1, further comprising: providing a guidewire, wherein the inserting of the shaft into the body lumen includes guiding the shaft into the body lumen using the guidewire.
 8. The method of claim 1, wherein the deflection mechanism includes a plurality of flat side-by-side metal segments of different lengths, wherein the changing of the shape of the deflection mechanism includes causing a curve in the plurality of flat side-by-side metal segments.
 9. An apparatus for displacing a portion of a body lumen, the apparatus comprising: a shaft; a first lumen within the shaft extending over at least a portion of length of the apparatus; an expandable member attached to the shaft and configured to expand within the body lumen; and a deflection mechanism configured to change shape by lateral deflection to cause a corresponding lateral deflection of the body lumen, wherein, when the deflection mechanism is in its undeflected neutral configuration, a distal portion of the deflection mechanism is along a first line defined between a proximal portion of the deflection mechanism and the distal portion, and wherein, when the deflection mechanism is changed in shape to a deflected configuration, a deflected portion of the deflection mechanism between the distal portion and the proximal portion curves away from the first line and then curves back toward the first line while the distal portion and the proximal portion are along the first line, wherein the expandable member surrounds the shaft such that at least a portion of the expandable member surrounds at least a part of the deflected portion of the deflection mechanism, and wherein the deflection mechanism is further configured to rotate circumferentially within the shaft.
 10. The apparatus of claim 9, further comprising a tube operatively coupled to the expandable member to inject a fluid into the expandable member to cause the expandable member to expand within the body lumen.
 11. The apparatus of claim 9, further comprising a second lumen within the shaft and operatively coupled to the expandable member to inject a fluid into the expandable member to cause the expandable member to expand within the body lumen.
 12. The apparatus of claim 9, wherein the first lumen within the shaft is operatively coupled to the expandable member to inject a fluid into the expandable member to cause the expandable member to expand within the body lumen.
 13. The apparatus of claim 9, wherein the expandable member includes a plurality of expandable segments serially located along the shaft, wherein each one of the plurality of expandable segments surrounds the shaft such that when each one of the plurality of expandable segments of the expandable member expands within the body lumen, the shaft is substantially centered within each one of the plurality of expandable segments.
 14. The apparatus of claim 9, further comprising: a guidewire configured to guide at least a portion of the catheter shaft into the body lumen.
 15. The apparatus of claim 9, wherein the deflection mechanism includes a plurality of flat side-by-side metal segments of different lengths and a contraction cable configured to cause a curve in the plurality of flat side-by-side metal segments when the cable is placed in tension.
 16. The apparatus of claim 9, wherein the deflection mechanism includes a plurality of flat metal segments of different lengths that are arranged face-to-face, and a contraction cable configured to cause a curve in the plurality of flat metal segments when the cable is placed in tension, wherein a first metal segment of the plurality of flat metal segments has a longest length of the plurality of flat metal segments, wherein a distal end of the contraction cable is attached to the first metal segment, and wherein at least a second metal segment of the plurality of flat metal segments is located between the first metal segment and the contraction cable.
 17. An apparatus for displacing a portion of a flexible target lumen, the apparatus comprising: a catheter shaft having a first catheter-shaft lumen within the catheter shaft, the first catheter-shaft lumen extending through at least a portion of a length of the catheter shaft; means for expanding a diameter of a first portion of the apparatus when the apparatus is, at least partially, within the flexible target lumen, wherein the means for expanding the diameter of the first portion of the apparatus is operably coupled to the first catheter-shaft lumen; and means for laterally deflecting the expanded first portion of the apparatus while within the flexible target lumen in order to deflect the flexible target lumen, wherein at least a portion of the means for expanding surrounds at least a part of the deflected portion of the catheter shaft, and wherein the means for laterally deflecting is configured to rotate circumferentially within the catheter shaft.
 18. The apparatus of claim 17, further comprising: means for guiding at least a portion of the catheter shaft into the flexible target lumen.
 19. The apparatus of claim 17, wherein the means for expanding the diameter of the first portion of the apparatus includes means for injecting a fluid into the means for expanding the diameter of the first portion of the apparatus.
 20. The apparatus of claim 17, wherein the catheter shaft is substantially centered within the means for expanding when the means for expanding expands within the flexible target lumen. 